Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!rutgers!cmcl2!phri!roy
From: roy@phri.UUCP (Roy Smith)
Newsgroups: comp.periphs
Subject: Re: SCSI
Message-ID: <3896@phri.UUCP>
Date: 25 Jul 89 04:18:00 GMT
References: <15666@ut-emx.UUCP>
Reply-To: roy@phri.UUCP (Roy Smith)
Organization: Public Health Research Inst. (NY, NY)
Lines: 26

In <15666@ut-emx.UUCP> croley@walt.cc.utexas.edu (David T. Croley) writes:
> any comments about SCSI-2, SCSI controllers, etc. would be most helpful.

	From what I can tell, SCSI falls under the catagory of "the nice
thing about standards is that you have so many to choose from".  The theory
is supposed to be that if it's a SCSI peripheral, you can plug it into a
SCSI system and it should work, modulo some driver software.  Well that's
nice, except that Sun does something funny with the ground pins.  And Apple
uses a non-standard 25-pin connector instead of the 50-pin amphenol.  With
Apple, you're supposed to use a 25-to-50 pin "system cable" to get to the
first device.  Except, now I see Mac peripherals (notably CMS disks) with
25 pin connectors on them, so you need a 25-to-25 cable to the first disk
and then your 25-to-50 cable to the rest of the SCSI chain.  But wait, what
about this neat HP scanner SCSI interface box; it's only got a single SCSI
connector, so it's got to be the last thing on the chain with a feed
through terminator, unless you've got stacking SCSI cables.  And some disks
have internal terminators which you have to remove, or make sure they are
at the end of the chain.

	SCSI's a great idea, but with everybody taking pot-shots at the
standard, it's quickly turning into a mess, just like RS-232-C.
-- 
Roy Smith, Public Health Research Institute
455 First Avenue, New York, NY 10016
{att,philabs,cmcl2,rutgers,hombre}!phri!roy -or- roy@alanine.phri.nyu.edu
"The connector is the network"